When a baby experiences sudden shaking or tremors, parents often worry about their baby’s health and safety. While some instances are temporary and harmless, others can signal a more serious underlying health issue. This article clarifies the various reasons behind a baby’s shaking, helping parents differentiate between normal occurrences and situations that warrant medical attention.
Understanding Normal Baby Shakes
Many instances of infant shaking are a normal part of development and do not indicate a serious problem. A newborn’s nervous system is still maturing, meaning the pathways from the brain to the body are not yet fully developed. This immaturity can result in jerky, twitchy, or shaky movements, often diminishing as the baby grows, typically by one to two months of age. These are known as physiological tremors or jitters.
Physiological tremors often manifest as subtle quivering in the chin, hands, or legs. These movements are usually brief and stop when the baby is comforted, held, or their position is changed. For instance, gently holding a trembling leg still will typically make the tremor cease, which helps distinguish it from a seizure.
Another common and normal reflex is the Moro reflex, also known as the startle reflex. This involuntary response occurs when a baby is surprised by a sudden stimulus, such as a loud noise or a feeling of falling. The baby will extend their arms and legs outwards, arch their back, and then pull their arms back in, often accompanied by a cry. This reflex is present at birth and usually disappears by three to six months of age.
Babies can also shiver, just like adults, when they are cold. This is the body’s natural mechanism to generate heat. If a baby is shivering, checking their temperature and ensuring they are dressed appropriately can help determine if cold is the cause. Brief, irregular movements, or jitters, might also be observed during sleep transitions, when a baby is excited, or when they are hungry. These movements are short-lived and resolve on their own.
Medical Reasons for Shaking
While many instances of shaking are benign, certain medical conditions can cause a baby to shake and require medical evaluation. One such condition is low blood sugar, or hypoglycemia, which occurs when there is not enough glucose in the blood to fuel the brain and body. Symptoms in newborns can include shakiness or jitters, a blue or pale tint to the skin, lethargy, poor feeding, and in severe cases, seizures. This is a concern for infants of mothers with diabetes, premature babies, or those with certain metabolic disorders.
Seizures are another medical cause of shaking and involve abnormal electrical activity in the brain. Unlike normal jitters, seizure-related shaking is typically rhythmic and cannot be stopped by holding the affected limb. Seizures in infants can manifest in various ways, including repeated jerking movements of the arms or legs (clonic seizures), stiffening of the body (tonic seizures), or subtle signs like eye-rolling, staring, or unusual mouth movements.
Febrile seizures are a common type of seizure in young children, occurring with a high fever, usually between six months and five years of age. These seizures often involve uncontrollable shaking, loss of consciousness, and can last from a few seconds to several minutes, typically under 15 minutes. Simple febrile seizures usually do not cause long-term harm or brain damage.
Neonatal abstinence syndrome (NAS) can also cause shaking in newborns. This condition occurs when a baby experiences withdrawal symptoms from substances, most commonly opioids, exposed to in the womb. Symptoms of NAS can appear within days or weeks after birth and include body tremors, seizures, high-pitched crying, irritability, feeding difficulties, and disturbed sleep. Less common neurological conditions, such as electrolyte imbalances like low calcium (hypocalcemia), intracranial hemorrhage (bleeding in the brain), or severe infections like meningitis, can also present with tremors or seizures and require immediate medical attention.
Signs Your Baby’s Shaking Needs Attention
Distinguishing between normal infant movements and those that warrant medical concern involves observing specific characteristics and accompanying symptoms. If a baby’s shaking is prolonged, lasts more than a few seconds, or occurs frequently, it warrants closer observation. While normal jitters typically subside quickly, persistent or repetitive movements may suggest a different origin.
A sign of concern is if the baby becomes unresponsive or loses consciousness during the shaking episode. If the baby does not react to voices, touch, or comforting measures, or if their eyes roll back or become fixed, this indicates a need for immediate medical evaluation. Changes in breathing patterns, such as pauses in breathing (apnea), very rapid breathing, grunting, or gasping, coupled with shaking, are also red flags.
Observe any changes in the baby’s skin color, such as turning pale, blue, or blotchy, especially around the lips or nail beds. These color changes, alongside shaking, can indicate a lack of oxygen or another serious issue. The presence of a fever, particularly in infants under six months, accompanying shaking or seizure-like activity, indicates a need for medical attention.
If the shaking does not stop when the baby is comforted, held, or fed, or if the movements appear stiff or rigid, this differentiates them from benign tremors. Any shaking accompanied by irritability, a high-pitched cry, unusual lethargy, or difficulty waking the baby also signals a need for prompt medical assessment.
What to Do When Your Baby Shakes
When your baby shakes, observe the episode closely. Note details such as how long the shaking lasts, what body parts are involved, and any other symptoms present, like changes in breathing, skin color, or responsiveness. This information will be valuable for medical professionals. If the shaking is brief and the baby appears otherwise well and responsive, try to comfort them by holding, swaddling, or feeding.
If the shaking is prolonged, if your baby becomes unresponsive, loses consciousness, or has difficulty breathing, seek urgent medical attention immediately. Call emergency services or go to the nearest emergency room. If the baby is having a seizure, gently lay them on their side in a safe area, remove any nearby objects, and do not try to restrain the movements or put anything in their mouth. Timing the duration of the seizure is also helpful for medical assessment.
For concerns that are not immediately life-threatening, contact your pediatrician for advice. This includes instances where the shaking seems unusual, occurs repeatedly, or is accompanied by symptoms like fever, unusual lethargy, or persistent irritability. Recording a video of the shaking episode can be helpful, as this visual evidence can assist your doctor in making an accurate diagnosis. If you are worried about your baby’s shaking, seeking professional medical guidance is the best course of action.